Guillermo del Toro says Corey Stoll being able to lose his hair was key to his 'Strain' character

FX's new vampire series "The Strain" has just begun its first season, but co-creator Guillermo Del Toro was not shy about discussing where the story would lead in future episodes during his appearance on a very packed panel at the Television Critics Assn. press tour on Monday.

The Mexican director of "Pan's Labyrinth" and "Pacific Rim" joined his co-creator Chuck Hogan and show runner Carlton Cuse on stage with 10 members of their cast. And while there was much discussion about Del Toro's memorabilia-packed houses, it was an innocent question about leading man Corey Stoll's wig on the show that revealed a lot about where things are going.

In the series, Stoll plays Ephraim Goodweather, the head of a CDC team tasked with investigating a plane full of dead bodies on the runway at JFK airport. What we soon learn is that the bodies are actually infected with a vampiric breed of worms that quickly spreads to the living populace. Stoll is a familar face to fans of his run on the Netflix series "House of Cards," but he looks different in "The Strain" because of the prominent hairpiece his character wears. When asked about it, the famously bald Stoll joked that it was nice to let his "real hair" grow.

But Del Toro revealed that the addition of hair to the character was key for the development of the show.

"If you know where it's heading, the character needed to be able to change his look so he could blend into the population and not be seen," del Toro said. "Unless he grows a beard or has an eyepatch, we needed somewhere to go."

At this summer's Television Critics Assn. Press Tour, actors, directors and other insiders give insight into their upcoming television programs.

But how does being bald help someone blend into the population? Well, does it clarify matters to know that the vampires in their final state are completely hairless? So it looks as if Goodweather's attempts to get a handle on the vampire menace will go south pretty quickly.

"I was skeptical [of the wig] at first," Stoll said. "The assumption was that I needed to fit a mold. But it was the opposite."

The series is based on a trilogy of books co-authored by del Toro and Hogan, but Cuse cautioned that anyone familiar with the books should not automatically assume they knew every twist of the show.

"The way things happen and the fate of the characters is not completely determined by the books," he said.

Del Toro elaborated, "We wanted to hit highlights of the books. Sometimes we hit them early; sometimes we hit them much later."

The director said he first pitched the project back in 2006, but executives at the time couldn't wrap their head around the idea of horrific, monster-like vampires. They could only think of them as sexy. One suggested he do it as a comedy. Del Toro wisely kept the project to himself until the time was right.

"Vampires are truly revolting parasites," he said. "They drink you like a Capri Sun. They don't hold you and say, 'Now I give you my life.' No, they crush you and throw you away."

In that regard, Del Toro himself is very un-vampire-like. To kick off the panel, he was asked to describe his house, which is actually two houses, side-by-side, filled to overflowing with the director's vast collection of toys, books and other ephemera. It's 11,000 square feet, with 11 different libraries and shelves all constructed by the director himself. He also has his first toy from the age of 4 all the way up to his latest toy, which he had just picked up the morning of his TCA panel.